This is nice and all, but as an indie developer, I've never needed to design my app layouts separately from my actual project in Xcode. Maybe I'm going about this development thing all wrong - but as a one-man-band, it would take too much time to design my app layouts outside of the coding environment IMHO.
In case they work.. I've got two SPM modules besides two projects inside a workspace and its impossible to make it work. Complaining about files not being part of any build. Files which are part of other packages which should not be built in the first place!?!